Rotary pump



A. E. SIMPSON Ronny PUMP Filed June 2. l1.924 2 Sheets-$11661 1 April 3, 192s. 1,664,644

lff V mi April 3, 1928. 1,664,644

A. E. slMPsoN ROTARY lPUMP Lil) Patented Apr. 3, 1928.

UNITED STATESA PATENT oEFicE.

ARTHUR E. SIMPSON, OF,WEST

FRANKFURT, ILLINOIS, ASSIGNOR OF ONE-SEVENTH TOH. L. WEBB, ONE-SEVENTH TO J. M. HARRIS, ONE-SEVENTH TO B. H. WEBB, ONE- SEVENTI-I TO T. M. SILKVJOOD', .ONESEVENTH T0 R. P. BLAKE, AND ONE-SEVENTH TO C. E. PITCHFORD, ALL F WEST FRANKFURT, ILLINOIS.

ROTARY rum?.

Appucauon filed June 2, 1924. seriai No. I217,307.

VMy invention relates to improvements in rotary pumps and has for itsprimary object a rotary pump which will' deliver a maximum amount of liquid with a minimum amount of power and in which pulsationsof delivery are practically eliminated.

A further object is to construct a rotary pump which can berun either right or left hand by merely removing and reversing the rotor.

A still further object is to construct a rotary pump in which the pistons are not dependent on centrifugal force or mechanical movement to hold them against the cylinder, but in which the suction and the fluid pump have a tendency to cause the pistons to move outwardly landtit ltightly against the cylinder. Y

In the drawings:

Fig. 1 is a sidey elevation of my device with the driving means removed;

Fig. 2 is a top plan view of the same; Fig. 3 is a vertical cross section taken on the line 3-3 of Fig. 2;

Fig. 1 is a horizontal cross section taken on the line 4.-4 of Fig.' 1 with the rotor removed;

Fig. 5 isa top plan -view of one of the pistons; f

Fig. 6 is a. bottom plan view of the same;

Fig. 7 is an enlarged view of the rotor looking atthe same in the direction of the arrow A of Fig. 11;

Fig. 8 is an enlarged view of the rotor looking at the same in the direction of the arrow B of Fig. 11; l V

Fig. 9 is an enlarged fragmental section of the rotor and piston as viewed from the top with the piston in closed positionA and illustrating the passages;

Fig. 10 is an enlarged fragmental section of the rotor and piston showing the passages on the underside of the piston ;Y

Fig. 11 is an end elevation of the rotor with the pistons removed; and

Fig. 12 is an end elevation ofthe pump and driving mechanism when. assembled ready for operation. l

In the construction `of my device I employ a housing 13 which comprises a. base 14, and a. cylinder 15. jFormedin the base 14 ber.

are openings 16 and 17 which are threaded to receive` pipes 18 and 19, and which are thek delivery and suction pipes respectively." The screw threaded opening 17 opens into a chamber 20, which will hereafter be termed the suction chamber, while thevscrcw threaded opening 18 opens'into a chamber 21, which will hereafter be termed the delivery chamber. The chamber k20 has screw l extending therefrom and into the cylinder 15 a plurality of-openings or ports 22. `These openings or ports are ypreferablyy elongated and are of such size that their combined areas will equal the area of the pipe 19. Vhile the chamber 21 communicates with the cylinder 15 by means of 'similar openings*k orv ports 23 whichare similarly constructed.

ment wall 24. n Y

The housing 13 is provided with screw i threaded openings 25 into which cap screws 26 fit. These capfscrews are for the purposeV lBetween the chambers 21 andy 20 is an abut- Y provided with a gland 29 through which a shaft 30 extends.. The gland 29 however, isso positioned on each head as to be eccentric to the bore ofthe cylinder 15, so that the rotor 31 'which is secured to the shaft 30 will fit closely against the abutment 24. This is necessary in order to divide the cylinder into a suction and a delivery cham- The cylinder 15 is further provided on its interior face `with arcuate recesses 32 and 33, these recesses commencing at the openings 22 and 23 respectively, and gradually decreasing in depth as they extend from the respective openings. This is-clearly illustrated in Fig. 3 andthe purposethereof will be described in detail later.

The rotor 31 is also provided with cutaway portions 35 and with sockets 36. These cut-away portions and sockets permit thev insertion of pistons 37. The pistons 37 are provided with cylindrical projections 38 cylinder. v

y'or ribs in between.l

pressions are filled with a bearing` metal 42' which is preferably softer than the material out of which the housing 13 and the pistons 37 are formed, and if not softer, at least of` a diiferent metal so that friction is reduced. It is a well known fact in physics that vtwo like metals runnin on each other create more frictiony than unlike metals. llVhere a softer filling is used the ribs 4l prevent rapid wear; and by their diagonal distribution prevent cutting of ridges within the The edge 48 of the pistons 3'? acts as a pushing edge and is provided with V shaped grooves 44, which grooves are in alinement with grooves 45 cut in the edge 4G of the recesses 35. The underneath face 47 of the pistons '37 is likewise` provided with V shaped grooves 48which are in alineinent `with similar grooves 49 cut in the face 50 of the recesses 35. The grooves 45 and 49 and 44 and 48 are continuous so that any fluid `which passes into the grooves 44 and 45 will also pass into the grooves 48 and 49. The purpose of this will be explained in-del'ail later.

Secured to each gland 29 is ya packing nut 5l by means of which the shaft 30 isV so packed as to prevent any leakage. The heads 27 are provided with packing rings 52 which are adjusted by means of screws 53 and are for the purpose of preventing leakage between the cylinder heads and the rotor.

The pump `vis preferably mounted on a table 54 which is supported by legs 55, these legs in turn supporting the motor or other source of power 56. Secured to the shaft 8() is a pulley 57, while the motor carries a pul- `ley 58,.,and around Ythese two pulleys passes abelt 59. The belt is given its proper tension by means of an idler 60 which is carried by the table 54 and which is preferali ly controlled by means of. a counterweight (il, although if desired, a sliiringtension for the idler maybe used, the sole purpose of the idler being to keep the belt suihciently tight to operate the pump and take care .of any stretch in the belt. y

I may however, desired, connect my pump directly to the source of power or use gearing or other well known means to drive the pump without departing from the spirit of my invention.

' It will be .noted from Figs. Sand 4 that the openings 22 and 23and, the recesses32 and 33 are spaced apart/'so as toI leave ridges These ridges or ribs form a continuation of the bore of the cylinder 15 so that the pistons 37 will'havc a' continuous` circular support throughout their rotation. j' Y The operation of my device is as'follows zy l Y .1

After'the pump is assembled a-ndconn'ect-` ed up, the rotor is'iotatedinthejdirection of the larrow in Fig.v 3. vIn this'connection it fis-cssential to note that the only point of coni' act between the rotor and the cylinder is the abutment 24. As soon as the piston passes the abutment 24 it drops downward by gravity and as it continues to rotate follows thebore of the cylinder and gradually moves away from the center of rotationor out of the rotor. i

The piston fitting snugly against the wall of the cylinder creates a suction behind it which draws the fluid to be pumped into the chamber 2O and from there through the openings 22 into the cylinder. This suction also tends to hold the piston against the cylinder wall, or in other words prevents gravity from causing the piston to drop backward into the pocket orrecess 3,5. As soon as vthe next piston passes the abutment, this operation is `repeated with the addition that some of the iluid thus trapped between the two pistons enters the passage waysformed bythe groovesv44 and 45 and 48 and 49.

The fluid thus entering fills up the space bctween the pistou and the bottom of the recess 35, and further assists in holding the piston tightly against the periphery of the cylinder@ As'soon as the piston has passed the point on the periphery of the cylinder' directly opposite the abutment 24, it is gradually forced into the pocket. This is due to the eccentric mounting of the rotor and as the piston is thus forcedy in, any fluid which is in the space between the bottom ot' the recess 35 and the face 47 of the'piston is forced out through the passage way 'assum-k fing a reversed direction from that in whichV 1t enters.

It is very essential that 'provisionbe made to permit'the fluid to escape readily as otherwise there "would be a possibility of trapping some of the fluid and cause it'to forni a rcushion which would prevent the entire collapse of the piston into the rotor and set up a great amount of useless friction.

By the peculiar construction'ot' the outlet both pistons delivering fiuid at the same time. In fact as soon as the delivery faee'43 of one piston commences to ride on the ridges formed between the openings 23, communication is established with. the liquid which is being pushed by the other piston.V Thispermits a slight amount ofV fluidto pass into the grooveBS and as thisamouut Vand intake, Yand especially thelocation of y `the grooves 32 and 33 1t is possible to have increases it also has a tendency to force the `V`V piston nearest the discharge opening 23l into the pocket, thus relieving friction to a great extent. And after one piston has passed the abutment it will continue to have a sucking action until the succeeding piston has reached a point Vpast the ribs or ridges be tween the groove 32. By this construction there are no sudden pulsations either of suction or delivery because by the arrangement of the grooves the suction and delivery of each piston is overlapped by the suction and delivery of the other.

l have also discovered that by utilizing the grooves 32 and 33 that the capacity of the pump can be practically doubled, as well as permitting the pump to be run with less power.

li-/fy pump can be readily reversed in action, thatis, the suction and delivery directions of the pump can be readily changed by merely removing the rotor andreversing its position in the housing and rotate it in the opposite direction to that shown in Fig. 3, because there are no check valves used in this pump, as is the case in reciprocating pumps.

lt will further be noted. from Fig. 3 that the end i3 of the pistons 37 presents a liat face which extends substantially radial to the cylinder when in contact against the cylinder wall, thus the fluid being pumped has the tendency to hold the piston against the cylinder. This tendency of the fluid is assisted by the relatively large spaces between 'the surfaces t3 and 46 thus readily permitting the passage of fluid .into the space 'as the piston swings out from the rotor, and also allowing its ready ejectment when the piston is collapsed into the rotor, which collapse is caused by the eccentricV mounting of the rotor in the cylinder.

Having fully described my invention, what l claim is:-

'1. A rotary pump comprising a housing having a base, a cylinder formed in said housing above said base, a rotor eccentrically mounted `in said cylinder, a pair of substantially triangular pistons pivotally mounted at their rear ends and diametrically opposite each other in said rotor andadapted to contact with the periphery of said cylinder, a plurality of intersecting ribs formed on the outer face of said pistons, bearing metal located between said ribs, a

suction chamber formed in said base, a de-y livery chamber formed in said base, a plurality of laterally spaced parallel passages gradually increasing 1n depth and having ports therein at their point of greatest depth for connecting the suction and delivery chambers with the interior of the cylinder, and an abutment located between said ports and said passages and the chambers inthe base, said abutment being in constant contact with the rotor.

2. A rotary pump. comprising a housing having a base, a cylinder formed in said housing above said base, a cylindrical rotor eccentrically mounted in said cylinder, a pair of substantially triangular pistons pivotally mounted at their rear ends in sai rotor and adapted to contact with the periphery of said cylinder, a suction chamber formed in said base, a delivery chamber formed in said base, a. plurality of laterally spaced parallel passages gradually increasing in depth and having ports therein at their point of greatest depth for connecting the suction and delivery chambers with the interior of the cylinder, means formed in the rotor and piston for permitting some of the iiuid being pumped to forcibly pass to Vthe underside of said pistons for holding the same against the periphery of the cylinlder, and an abutment integral with said housing and located between said ports and chambers, said abutment being in constant contact with the rotor.

3. A rotary pump comprising a housing having a base, a cylindrical bore formed in said housing, heads located on opposite sides of said housing for closing said bore, a rotor having diametrically opposite, substantially triangular recesses extending across its periphery eccentrically and rotatably mounted in said casing, pistons substantially triangular in longitudinal section pivotally mounted at their reduced ends in said recesses, passageways formed intwo faces of said recesses and in the adjacent faces of said pistons for permitting fluid being pumped to freely vpass to and from thev underside of said pistons, a suction chamber formed in the base, a delivery chamber formed in the base, an abutment between said chamber and terminating Hush with the cylindrical bore, a plurality of spaced channels gradually decreasing in depth formedin said bore and extending at right angles to said abutment and in opposite directions therefrom, said channels extending only partly around said bore, and ports formed in said channels at their point of greatest depth and communieating with the suction and delivery chambers for permitting liquid to pass therethrough to and from the cylindrical bore.

In testimony whereof, I have signed my name to this -specication ARTHUR E. SIMPSON.- 

